PIC18F2450_08 Datasheet, PDF (14/324 Pages) Microchip Technology – 28/40/44-Pin, High-Performance, 12 MIPS, Enhanced Flash, USB Microcontrollers with nanoWatt Technology

PIC18F2450/4450
TABLE 1-2: PIC18F2450 PINOUT I/O DESCRIPTIONS
Pin Name
Pin Number
Pin Buffer
SPDIP,
SOIC
QFN
Type
Type
Description
MCLR/VPP/RE3
MCLR
VPP
RE3
OSC1/CLKI
OSC1
CLKI
1 26
Master Clear (input) or programming voltage (input).
I
ST
Master Clear (Reset) input. This pin is an active-low
Reset to the device.
P
Programming voltage input.
I
ST
Digital input.
9
6
Oscillator crystal or external clock input.
I Analog Oscillator crystal input or external clock source input.
I Analog External clock source input. Always associated with pin
function OSC1. (See OSC2/CLKO pin.)
OSC2/CLKO/RA6
OSC2
CLKO
RA6
10 7
Oscillator crystal or clock output.
O—
Oscillator crystal output. Connects to crystal or resonator
in Crystal Oscillator mode.
O—
In select modes, OSC2 pin outputs CLKO which has
1/4 the frequency of OSC1 and denotes the instruction
cycle rate.
I/O TTL General purpose I/O pin.
Legend: TTL = TTL compatible input
ST = Schmitt Trigger input with CMOS levels
O = Output
CMOS = CMOS compatible input or output
I
= Input
P
= Power
DS39760D-page 12
© 2008 Microchip Technology Inc.